Area measuring apparatus and method



MC. 19, ww. LBOWLES 2,184,156

AREA MEASURING APPARATUS AND METHOD Filed May 6, 1931 /NVENTOR 2 Edward L. Bow/es ATTORNEY Patented Dec. 19, 1939 2,184,156 AREA MEASURING APPARATUS AND METHOD 4 Edward Llndley Bowles, Wellesley Farms, Mass., assignor to Stockton Profile Gauge Corporation, Lowell, Mesa, a corporation of Massachusetts Application May 6, l

The present invention relates to the art of measuring areas, and more particularly to the areas of hides.

The invention will be explained in connection t with the accompanying drawing, the single figure of which is a diagrammatic view illustrating the principle of the invention.

A scanning disk 2 is interposed between a reiiecting support or background t for a hide t,

W or other article the area of which it is desired to measure, and a lamp or other source it of preferably constant illumination; The rays it of light from the source it are caused to pass through a lens or lens system it and, after W passing through the scanning disk 2-, and through a lens or lens system it, strike the hide t and become absorbed, or strike the uncoveredportion of the background t and are reflected as at it. The rays it reflected from the unobstructed pp portion of the background t are concentrated by a condensing lens it and strike the electronernitting cathode ll of a light-sensitive cell t.

The rays striking the cell t may be caused to eiiectthe incation of the area of the hide gt through the combination with the cell t of: an amplifier it, a relay contact member ti, a clutch ti and a register or counter M. I

During the scanning process the area-registering instrument at will integrate the area of to the hide since it will operate only when the reflected light it is reduced by the presence of some elemental area of the hide. When the incident light it strikes the background, which may deliberately be made a much better resg hector, the integrating mechanism W is momentarily disconnected during the period of incidence. The indication of the calibrated registering mechanism will be a direct measure of the area of the hide.

id The support 6 and the hide t are shown vertically disposed, in order that the grease from the hide shall fall to the floor, and not upon the support, thus preventing dirt or foreign matter of substantially diflerent reflection properties it from collecting on the support 5.

The anode it of the photo-electric cell t is connected by a conductor 2% with the grid ii of the amplifier tube 25, which is provided also with the usual filament 2i and plate 29; The

to cathode ll of the cell t is connected by a conductor l8, inseries with a battery 20!, with the filament or cathode 21!. A resistor 22 is connected between the filament 21 and the grid 2|. A resistor 34 with resistance of large value com- Ud pared with the resistance of the relay coil 3? 931, Serial No. 535,405

that substantially all of any change of plate current will pass through the relay coil it. The

coi1 31 is connected, in series with a battery it, 6

across the resistor 3t for the purpose of balancing the steady plate current of the tube 25 out of the coil ti and operates the relay contact member ti for controlling the magnetic clutch it. The clutch, in turn, operates the calibrated l counter t that may be driven, as by gearing M, from the same motor t9 that drives the scanning disk 2. It is-assumed, for simplicity, that the motor is operated at constant speed.

Assuming, by way of example, the area of illumination of the projection on the background tot each aperture ti of the -scanning disk to have a unit width, and the average distance of the horizontal projection between successive slots, at the time that they occupy their uppermost position, in front of the lens It, as d units, then the projection on the background tot each aperture ti wil1 travel d units at each excursion of an aperture across the field of light rays in front-of the lens it. A unit bundle of 26 rays will thus move pivotally from the lamp it across the support t a distance d units, and thus scan a strip 1 d units in area. The background it, then, will be scanned in terms of element strips d units in area, one such strip for each 30 aperture of the scanning disk 2. It is of course understood that there are many methods of scanning an image and the one selected is only for illustration. The photo-electric cell t will, therefore, be subjected substantially wholly to light passing through each aperture and reflect- .ed from the background 6. There will be a negligible amount of reflected light from the hide. The photo-cell as shown may be assumed to be so connected that with appreciable light inci- 40 dent upon its cathode ll, corresponding to no (hide) obstruction on the background 6, there will be no appreciable current in relay coil3l. Thus, the relay contact member ll would remain open and the magnetic clutch 43 would 45 not engage the register 65 with the motor and scanning disk. If there were no hide or other relatively non-reflecting surface 8 on the reflecting background 6, the object-free area B in being scanned would cause the relay contacts 4| to remain open and thus quite properly no area would be registered. Suppose, however, that a hide 8 is in position; then, as the scanningarea light moves across the background 6, the relay contacts II will remain open until the light 7 ing background against which is held a substanarea strikes the hide surface. When it strikes this relatively non-reflecting surface the photocell current will decrease, increasing the voltage on the grid 2i positively, thus increasing the' netic clutch 43. Duringthe traverse of an individual scanning aperture, the magnetic clutch will engage the register so long as there-is a relatively non-reflecting area in the path of this corresponding scanning light spot. For example, if the entire distance 'dof a single traverse is occupied by part of a hide, the calibrated register 45 will register d units of area. If the hide only intercepts a portion of this elemental traversed path, the clutch will engage the register only when this hide area is present. Thus, in a complete scanning, the register will have recorded the area of the hide in a very accurate manner, having measured or integrated it in terms of small increments. The integration, thus effected in terms or small, finite elements.

yields a total summation for the area of much greater accuracy than would be obtained were .the photo-electric cell 4 to be subjected to'the action of the reflection of radiant energy from the complete area 8 in one operation.

34) It should be emphasized that a feature of the present invention depends on difierences in the light reflected from the background 6 and the surface 8 to be measured held against this background. The relay contact member M is either open or closed, and the magnetic clutch is either connected or disconnected, depending on whether the light is reflected from the background 6 or from the surface 6 to be measured. The difierence in intensity of the light reflected from the background and that reflected from the area 8 to be measured is such that the cell 3 will cause the relay contacts iiv to be actuated only when a relatively small amount of light strikes it, that is, when the surface 8 to be measured is the 5 source of the reflected light. This implies, of course, that the light reflected from the area t to be measured is relatively small compared to the light reflected fromthe background 6. In fact, the difierence in intensity of the reflected light must be such that, when it comes from the background 6, the relay contact member 6 i opens, and .when it comes from the area to be measured the relay contact member iii closes.

The photo-electric cell may be subjected to any as desired color of light rays, as by use of a light filter (not shown) or it may be used with artificial light or daylight.

Modifications will readily occur to persons skilled in the art, and all such are considered to so fall within thespirit and scope of the present invention, as defined in the appended claims.

What is claimed is: e .1. Area-measuring apparatus having, in combination, a source oi rays, a background against as which is held the'article the area of which is to be measured, means for subjecting the article and the background to the rays from the source,

means for causing rays from continuously successive portions oithe article to produce efiects,

70 means for adding the said efiects, and means for rendering negligible the efiect produced by the background.

2. Area-measuring apparatus having, in combination, a source 01 light, a substantially reflecttially nonreflecting article the area of which is to be measured, a light-sensitive element, 11' cans for directing light along a path from the source to the background and the article and from the background and the article to the light-sensitive 5 element, a scanning disk interposed in the said path, and means for integrating the efl'ects produced upon the light-sensitive element to measure the area of the article.

3. Area-measuring apparatus having, in comm bination, a source of light, a light-sensitive element, means for directing light along a path from the source to the article the area of which is to be measured and from the article to the light-sensitive element, movable scanning means 15 interposed in the path, means for moving the scanning means to'subject successive portions of the article continuously to the action of rays from the source,'and means for integrating the eflects produced by the said light upon the light- 20 sensitive element to measure the area of the article.

4. Area-measuring apparatus having, in combination, a source of light, a light-sensitive element, means for directing light along a path from 25 the source to the article the area of which is to be measured and from the article to the lightsensitive eiement, movable scanning means interposed in the path, means for moving the scan ning means to subject successive portions of the an article continuously to the action of rays from the source, a counter, and means controlled by the light-sensitive element for actuating the counter to measure the area of the article.

5. Area-measuring apparatus having, in com- 35' bination, means for supporting an article the area of which is to be measured, a source of light, a light-sensitive element, means for directing light along a path from the source to the article the area of which is to be measured and so from the article to the light-sensitve element, movable scanning means interposed in the said path, means for moving the scanning means to subject successive portions of the article continuously to the action of rays from the source, 4,5 means for connecting the light-sensitive element in an electric circuit, and means controlled by the circuit for measuring the area of the article.

- continuously. successive portions of the area to produce like efiects andadding the like eiiects to measure the area.

'7. A method of measuring a substantially continuous area that comprises subjecting successive portions of the continuous area to a unit bundle of rays until the whole area has been subjected so to the rays, causing the continuously successive portions of the area so subjected to the rays to produce equal effects, and adding the efiectsso produced to measure the area.

8. Area=measurlng apparatus having, in combination, a source oi rays, means for subjecting the area to be measured to the rays from the source, means for causing the rays from continuously successive portions of the area to produce effects, and means for adding the eflects 50 pro 70,

duced to measure'the area.

9. Area-measuring apparatus having, in combination, a source of rays, means for causing a unit bundle of rays from the source to travel over continuously successive portions of the area until s,1e4,1ce

the whole area has been subjected to thefrays,

means controlled by the continuously successive portions of the area so subjected to the rays to produce chests, and means for adding the effects 5 so produced to measure the area.

i0. Area-measuring apparatus having, in combination,- a source of light, a light-sensitive element, means for directing light along a path from the source to the article the'area of which up is to be measured, and from the article to the light-sensitive element, scanning means interposed in the said path, a motor for driving the scanning means, means for operating the motor at constant speed, means for connecting the w light-sensitive element in an electric circuit,

' means for obtaining the area of the article, and

a clutch controlled by the circuit for connecting the area obtaining means to the motor.

, i i. A method of measuring a substantially g continuous area that comprises subjecting the continuous area to the action ofrays, causing the rays from continuously successive portions of the area to produce effects, and adding the effects so produced to measure the area of the as article.

12. Apparatus for measuring an area having, in combination, means for subjecting continuously successive portions of the area to the action of rays until the whole area has been subjected to the rays, means for causing the rays from the continuously successive portions of the area to produce like effects, and means for adding the like effects to measure the said area.

13. Apparatus for measuring an area having, in combination, means for subjecting continuously successive portions of the area to a unit bundle of rays until the whole area has been subjecteol to the rays, means for causing the continuously successive, portions of the area so subjected to the rays to produce equal efiects, and means ior adding the eflects so produced to measure the area.

ii. Area-measuring apparatus having, in comhination, a source of rays, a ray-sensitive ele ment, scanning means, means for causing the scanning means to subject successive portions of the area to be measured continuously to the action of the rays from the source, and means for integrating the effects produced by the scanmeasure the said area.

id. iii method oat-measuring the area of an article having a substantial and continuous area comprises holding the article against a background, subjecting the-article and the background to the action of rays, causing the rays iroin continuously successive mrtions of the continuous area of the articie and the background to produce effects, adding the said chests, and rendering negligible the effect oi the background upon the sum.

The herein described method comprising the steps of moving a beam of light at a constant'speed across a surface to be examined and thereby scanning a strip of known width across said surface, repeating said scanning operation on successive strips of said surface until sub-' stantiaiiy the entire area to be examined has been scanned, and causing the movement of said W beam across portions of said area having given characteristics to controi a counting operation in accordance with said characteristics.

17. That improvement in methods of measuring the area ofa surface which consists inmov- W ing a beam of iight at a predetermined speed ning means upon the light-sensitive element to across the surface to be measured and thereby scanning a strip of known width across said surface, repeating said scanning operation on successive strips of said surface until substantially the entire area to be measured has been scanned, 1' and causing the movement of said beam on and ofi said surface to control a counting operation.

18. A method of measuring the area of a relatively non-reflecting surface that comprises superposing the surface over a relatively reflecting background, scanning incremental strips of the surface by causing light'beams of predetermined width to travel over the background and the superposed surface, and causing the light beamsto control area-integrating operations only when they travel over the said strips, as contrasted to the background.

19. A method of measuring the area of a surface that comprises moving' a scanning beam of radiant energy across the surface along incremental strips of the surface to scan the said incremental strips, causing the movement of the radiant energy on and 0d the surface to control a counting operation, thereby to determine the lengths of the scanned strips, and integrating the said lengths in terms of units of area.

20. A method of measuring the area of 'a surface that comprises moving a scanning beam of radiant energy across the surface along an incremental strip of the surface to scan the said incremental strip, causing the movement of the radiant energy on and off the surface to control a counting operation, thereby to determine the length of the scanned strip, repeating the scanning' operation on other incremental strips of the surface, and integrating the lengths of the scanned strips in terms or units of area.

21. A method of measuring the area of a rela tively non-reflecting surface that comprises in-' terposing the surface before a relatively reflecting background, moving a scanning beam of radiant energy. of predetermined width over the background and the surface from one side of the background, and then across the surface along incremental strips of the surface to the other side of the background, to scan the said incremental strips, causing the movement of the radiant energy on and off the surface to control a counting operation, thereby to determine the lengths or the scanned strips, and calibrating the counting operation, in terms of the area of scanned strips to cause the counting operation to serve as a measure of the area of the surface traversed by the radiant energy.

22. Apparatus for measuring the area of a surface having, in combination, radiant energy means for scanning incremental portions of the surface, means controlled by the scanning means for determining a dimension of the scanned strips, and means controlled by the dimensiondetermining means for integrating the said dimension in terms of units of area.

23. Apparatus for measuring the area of a surface having, in combination, radiant energy means for scanning incremental strips of the surface, means controlled by the scanning means for determining the lengths of the scanned strips, and means controlled by the length-determining means for integrating the said lengths in terms of units of area.

2i. Apparatus for measuring the area of a surface having, in combination, means for moving a scanning beam of light across the surface along incremental strips of the surface to scan 7 of area.

the said incremental strips, photoelectric means ior determining the lengths of the scanned strips,

and means controlled by the photoelectric 'means' ior integrating the said lengths in terms/oi units 25. Area-measuring apparatus having, in combination, means for causing a scanning beam of light to impinge upon successive portions of a surface the area of which is to be measured to lo scan the s'ald successive portions, a iight sensi tive device positioned to; be responsive to the presence or absence of light reflected from the said surface, an amplifier controlled "by the light-sensitive device, a relay controlled by the 'ing the lengths into an amplifier, a counter calibrated in terms of area controlled by='the relay, and'means for synchronizinkthe operation of the flrst named means and the counter:-

EDWARD LINDLEY nos. 

